This invention relates to wastewater treatment processes, and more particularly, to such processes involving the removal of fats and heavy metal ions.
In recent years, an increasing importance has been placed upon treatment of wastewater from industrial processes in order to remove at least priority pollutants therefrom. The instant application concerns itself with the treatment of wastewater produced in wire drawing or rolling. Such wastewater normally contains emulsified synthetic fat and dissolved copper or other heavy metals. The direct discharge of these materials to the environment results in high organic loading, thereby increasing the biological oxygen demand and results in an increase in the toxic metal levels which have deleterious effects on aquatic and human life.
One of the methods currently used to treat industrial wastewater like that described above involves the evaporation of the waste to produce clean water and concentrated waste. The capital and operating costs required to support the evaporation process are quite high. Moreover, further treatment of the concentrated waste is required before disposal. Other processes involving the application of heat and the use of inorganic chemicals have been proposed, but these too have proven to be uneconomical and in some cases, only partially effective.
It is an object of the present invention to provide an improved wastewater treatment process which enables a substantially complete removal of synthetic fats and pollutant metal ions.
It is also an object of the present invention to provide an apparatus utilizing a single vessel in which both the separation of fat and metal ions can be accomplished.
It is a further object of this invention to provide a treatment process and associated equipment which will permit the use of existing equipment with reasonable modifications for the process described below.
Still another object of the present invention is to provide a process of the type described which will permit disposal of the treated wastewater through ordinary wastewater disposal systems, thereby reducing the bulk of material to be landfilled.